Answer this question truthfully
### Question: What causes Color blindness?
### Response: Color blindness occurs when there is a problem with the color-sensing materials (pigments) in certain nerve cells of the eye. These cells are called cones. They are found in the retina, the light-sensitive layer of tissue at the back of the inner eye. If you are missing just one pigment, you might have trouble telling the difference between red and green. This is the most common type of color blindness. Other times, people have trouble seeing blue-yellow colors. People with blue-yellow color blindness almost always have problems identify reds and greens, too.
Color blindness is often inherited genetically. It is most commonly inherited from mutations in a X-linked recessive fashion, but the mapping of the human genome has shown there are many causative mutations – mutations capable of causing color blindness originate from at least 19 different chromosomes and many different genes (as shown online at the Online Mendelian Inheritance in Man (OMIM) database at Johns Hopkins University).
Inherited color blindness can be congenital (from birth), or it can commence in childhood or adulthood. Some of the inherited diseases known to cause color blindness are:
Cone dystrophy Cone-rod dystrophy Achromatopsia (aka rod monochromatism, aka stationary cone dystrophy, aka cone dysfunction syndrome) Blue cone monochromatism Leber's congenital amaurosis Retinitis pigmentosa (initially affects rods but can later progress to cones and therefore color blindness)
Other causes of color blindness include:
Brain or retinal damage caused by shaken baby syndrome or other accidents and trauma which produce swelling of the brain in the occipital lobe Damage to the retina caused by exposure to ultraviolet light The drug hydroxychloroquine (Plaquenil), which is used to treat rheumatoid arthritis, among other conditions